Tiny liquid volcanoes that spray beams of charged particles could make space history next year.

They are one of two technologies vying to be the first to let cheap, miniature satellites called CubeSats fly in formation, switch orbits or voyage to other planets – feats usually reserved for large, expensive craft. They could even provide us with a global Wi-Fi system on Earth.

Paulo Lozano leads a team working on CubeSat propulsion at the Massachusetts Institute of Technology. He has been given the go-ahead to launch two propelled CubeSats in 2014 – one funded by the US Department of Defense, the other by private donors.

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Meanwhile, Benjamin Longmier at the University of Michigan in Ann Arbor, who leads a rival project, announced that his team also has private funding – and a slot to launch their CubeSat on a NASA rocket next year. The race is on.

CubeSats are made from off-the-shelf components. The initial aim was to make access to space easier and more affordable.

Each one weighs just 1 kilogram, has 10-centimetre-long edges and can hold components like sensors and cameras. They are typically put into low Earth orbit by a rocket, where they remain for around 6 months, before spiralling in and burning up in Earth’s atmosphere. Although they have made space accessible to groups who wouldn’t otherwise have been able to afford it – most recently a team of high-school students – CubeSats haven’t done much cutting-edge science. “They were considered like toys,” says Lozano.

Some CubeSats have basic steering, but getting them to change orbits, let alone visit other planetary bodies, requires new technology. That’s because even today’s most efficient propulsion method, the ion engine, doesn’t scale down to CubeSat size.

Instead, Lozano and his colleagues will propel their craft with an unusual substance called an ionic liquid, made solely of positively or negatively charged ions. In the engine, a reservoir of ionic liquid soaks into a porous, metal chip and forms tiny pools in the pores of spikes on its surface. When a small electric field is applied, these pools morph into cones, which amplify the electric field so that it is strong enough to pull away ions in a steady beam (see below).

The process is self-sustaining. Fresh liquid gets sucked onto the chip when ions are emitted, just as tree roots suck in water when vapour escapes the leaves. The result is an array of between 500 and 5000 focussed ion beams that stream from each of the eight chips on the CubeSat when the electric field – the strength of which acts as the engine’s throttle – is applied.

Lozano’s team have fired the thrusters in the lab and calculate that just 8 grams of ionic liquid will propel a 2 kilogram CubeSat and change its orbit by 100 kilometres. The team plans to test this in one of its launches next year. Eventually, the aim is to send such a satellite to an asteroid to collect a scoop of dust.

They have stiff competition. Longmier’s team have a rival propulsion plan. Their CubeSat Ambipolar Thruster, or CAT, uses xenon, like traditional ion engines. The difference is that the CAT adds an intense and carefully shaped magnetic field that stops xenon ions from hitting the engine walls and going to waste. Using a permanent magnet means that no power is required to produce the field. They say a future version could also use water instead of xenon, which would make it easier to refuel.

Longmier’s team began their first crowdfunding campaign on the Kickstarter website in July. Although they failed to raise their &dollar;200,000 target, the appeal prompted a private donor to offer to pay for the technology and a launch next year aboard a NASA rocket. They hope their propelled CubeSats will one day fly to Saturn’s moon Enceladus and Jupiter’s moon Europa, both of which hold water – and perhaps life. A fleet of CubeSats with propulsion in orbit around a planet or moon can do a lot of things that big expensive satellites cannot, such as monitoring several locations in the atmosphere at once.

Propelled CubeSats could even be useful back here on Earth. Creating a universal “satellite Wi-Fi”, like existing satellite phone coverage, would require thousands of big satellites, which is prohibitively expensive. But you could dump a thousand CubeSats in one place then spread them out to the right points, for a fraction of the price.

Longmier’s team has just launched a second Kickstarter campaign, which could fund some add-ons, including a camera. No matter what happens, the team already has enough money to launch and propel the CubeSat next year. “We might have a little space race on our hands,” says Longmier.